Multilayer components based on zinc oxide are generally known as varistors. Costly internal electrodes composed of silver and palladium (Ag, Pd) are generally used for electrical contacting of multilayer varistors.
Internal electrodes composed of a silver-palladium alloy are frequently used for reducing diffusion of the electrode material into the ceramic material during the sintering operation, as is known, for example, from the document U.S. Pat. No. 4,675,644A. The addition of palladium increases the melting point of the electrode layers in a suitable way, so that the electrode layer can be sintered together with the ceramic and diffusion of silver during sintering is reduced. However, the additional palladium has the disadvantage that palladium is very expensive.
In addition, varistors in which the reduction of the electrode layer during the sintering operation is countered by greater layer thicknesses of up to 10 μm are known, for example, from the document U.S. Pat. No. 4,959,262 A. These thick electrode layers have the disadvantage that delamination occurs to an increased extent due to different sintering behavior of the materials. In addition, thicker internal electrodes have a greater volume requirement, which is found to be troublesome in the case of very small components. An object to be achieved is to provide a multilayer component having improved properties and a process for producing an improved multilayer component.